1. Field of the Disclosure
The present disclosure relates generally to prosthetic hip joints, which include an acetabular cup positioned within a patient's acetabulum to serve as the socket for the hip joint. More particularly, the present disclosure relates to an explant system for removing the acetabular cup from the acetabulum.
2. Description of the Related Art
Prosthetic hip joints generally include a femoral component and an acetabular component, the acetabular component including an acetabular cup positioned in a patient's acetabulum which serves as the socket for the hip joint and receives the head of a femoral component. During a prosthetic hip joint revision procedure, the acetabular cup is removed from the acetabulum and replaced with a new acetabular cup.
An acetabular cup may be removed from an acetabulum in accordance with the method and apparatus described in U.S. Pat. No. 6,565,575 issued May 20, 2003, entitled “Method and Apparatus for Removing an Acetabular Cup,” the disclosure of which is hereby expressly incorporated herein by reference. U.S. Pat. No. 6,565,575 discloses a surgical kit including an osteotome instrument having an elongated handle shaft terminating in a head portion, a plurality of interchangeable osteotomes having curved blades of different lengths, and pivot elements, such as spherical heads, which may be attached to the head portion of the instrument. In use, the spherical head of the osteotome instrument is seated within a recess of an acetabular cup liner such that the end of the osteotome blade is disposed closely adjacent the rim of the acetabular cup. Thereafter, the handle shaft of the osteotome instrument may be pivoted and/or rotated to make several cuts with the curved osteotome blade which are closely adjacent the outer hemispherical surface of the acetabular cup, until the acetabular cup may be removed from the acetabulum.
An internally-threaded, entirely frustoconical metal adapter has been used with the instrument of the above-referenced U.S. Pat. No. 6,565,575. After dislocating a prosthetic hip joint, the metal implant head is disengaged from the hip stem of the hip prosthesis, and the adapter is fitted within the frustoconical bore of the metal implant head in which the trunion of the hip stem was previously fitted. Thereafter, the threaded end of the instrument of the above-referenced U.S. Pat. No. 6,565,575 is threaded into the adapter and the acetabular cup is removed using the implant head in articulation with the acetabular cup.
Disadvantageously, this arrangement relies on use of the implant head of the hip prosthesis having the acetabular cup which is to be removed, and requires multiple adapters of varying size that are dimensioned to be compatible with the various sizes of implant heads of the hip prostheses.